[FIX] website: prevent crash for non admin publisher when click on form

When editing a website form, a `search_read` request is fired on
`ir.model` model to get the list of possible form actions (create
ticket, create opportunity, etc.).
But since commit [1] in Odoo 15, non-admin users don't have read access
anymore on this model, leading to a traceback when clicking on a form in
edit mode.

Steps to reproduce (as designer):
- Install only website and login as admin
- Make "portal" user an internal user and give him "Editor and Designer"
  rights
- Login as "portal" user
- Enter edit mode on any page and drag & drop the form snippet, or
  simply go to /contactus page which already has one
- Click on the form -> Traceback

Steps to reproduce (as publisher/restricted editor):
- Install website_hr_recruitment
- Make "portal" user an internal user and give him the following rights:
  - Website: Restricted Editor
  - Recruitment: Administrator
- Login as "portal" user
- Go to a job page like /jobs/detail/experienced-developer-4
- Enter edit mode and drag & drop the form snippet
- It will crash

[1]: https://github.com/odoo/odoo/commit/5dc4cff60a557e14b08440c227423291c407899b



opw-3098097
opw-3101884

closes odoo/odoo#108680

Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>